Improvement in cupola-furnaces



E C ATKINS Cupola-Furnace.

No. 221,995. Patented. Nov. 25,1879.

UNITED STATES PATENT OEEICE.

ELIAS C. ATKINS,`()F INDIANAPOLIS, INDIANA.

IlVl PROVEM ENT IN CUPO LA-FU RNACES.

Specification forming part of Letters Patent No. 221,995, dated November25, 1879; application iled May 1, 1879.

To all whom it may concern:

Beit known that I, ELIAs C. ATKrNs, of the city of Indianapolis, countyof Marion, State of Indiana, have invented certain new and u'sefulImprovements in Blast-Furnaces for` furnace in which the process ofreducing ores and refining their metallic product can be car- ,ried onwithout shifting such product to another furnace for refining, as hascommonly been done in the plant heretofore employed for these purposes;and the invention consists in the construction of a blast-furnace with aseries of radiating curved tuyeres surrounding and entering the hearthat a point near its bottom, by which a blast of air may be forcedthrough the molten metal within the furnace, and in certain otherdetails of construction, which will be hereinafter fully described, andthen specifically pointed out in the claims.

The hearth or crucible Aof the furnace is made slightly concave, and ofany suitable refractory material. It is provided at its lowest pointwith a tap-hole, a, through which the molten metallic contents arewithdrawn whenever desired.

The outer casin g of the furnace is formed of two concentric cylinders,b and b', having, preferably, a water-space, w, between them. Within thecylinder bis placed the furnacelining B, constructed of fire-brick orother suitable material.

Concentric with the outer casing, b', is an additional metallic case, c,which incloses the air-chamber D. This chamber is also further inclosedin a refractory non-conducting covering, c', which lines its innersurfaces and prevents injury from the influx of molten metal when theblast is shut o, and further prevents loss of heat when a hot-blast isemployed for working the furnace.

To one side of the air-chamber is attached the inlet-pipe E, throughwhich the supply of compressed air in the air-chamber is kept up. Thispipe E is provided with a stop-valve, F, by means of which the supply ofair is regulated or wholly shut off at will.

From the concave hearth A of the furnace extends a series of radialcurved tuyeres, e,

their outer ends enlarged and terminating in the bottom of the air-chamber D, the curvature of which bottom, as well fas that of the tuyeres,being substantially the same as that of the hearth A.

The holes through the water jiaclret fw, through which the Vtuyeres passon their way from the air-chamber to the furnace,.are much larger thanthe tuyeres, so as to allow the latter to be completely surrounded by alayer of refractory material continuous with the lining of the furnaceand air-chamber.

An openin g, d, through the several casings of the furnace, forms aslag-hearth, through which the slag and scoria are allowed to flow offas produced during the workin g of the furnace.

1t will be evident that the water-j aclzet may be dispensed with, ifdesired, and its place supplied by fire-brick or other refractorymaterial, without departing from the principle involved in my invention;but I prefer the water-jacket, as it produces a more durable andpleasant-working furnace.

The method of operating this furnace is as follows: The charge is put inin the ordinary manner of charging blast-furnaces, :and as the fusedmetal reaches the bottom it is continually agitated by the blast, whichenters at its very bottom with sufficient force to prevent the moltenmetal from backing up the tuyeres.

The action of the air upon the fused mass of metal causes a partialseparation of the baser portion, which will be thrown to the top, andwill pass off with the slag, which is drawn off after first closing thestop-valve, thus leaving the air-chamber lled with air of a densitysufflcient to prevent the metal from entering the tuyeres. The metalbeing thus left at rest,

the slag and oxidized portions of the base metals, which have risen tothe top, are drawn 2 g @Mees off through the slag-hearth. The blast isthen again turned on and the operation repeated.

When it is desired to draw off the refined metal, the tap-hole a isopened and the metal drawn oi into suitable molds. The tap-hole is thenclosed and the operation of Ithe furnace continues.

Having thus described my invention, I claim as new, and desire to secureby Letters Patent, the following:

The combination7 in a blast or cupola furnace7 of the concave hearth,curved inclined tuyere, entering near the bottom, the direction whereofcorresponds with the curvature of the hearth, blast-box, andwater-chamber intervening between the blast-box and interior lining,substantially as and for the purpose specied.

ELIAS C. ATKIN S. Witnesses MERRITT POTTER, GEORGE G. EARLE.

